Microwave antenna with cooling system
View Patent ↗According to one aspect of the present disclosure, a microwave antenna assembly is disclosed. The antenna assembly includes a feedline having an inner conductor, an outer conductor and an inner insulator disposed therebetween and a radiating portion including a dipole antenna having a proximal portion and a distal portion. The antenna assembly also comprises a sheath disposed over the feedline and the radiating portion defining a chamber around the feedline and the radiating portion. The chamber is adapted to circulate coolant fluid therethrough. The antenna assembly further includes a connection hub having cable connector coupled to the feedline, an inlet fluid port and an outlet fluid port. The connection hub includes a bypass tube configured to provide for flow of the coolant fluid from the cable connector directly to the outlet fluid port.
1. A microwave antenna assembly comprising:
a hub;
a cylindrical sheath extending distally from the hub, the cylindrical sheath defining a chamber;
a feedline configured to deliver microwave energy, the feedline including an inner conductor, an outer conductor, and an inner insulator disposed between at least a portion of the inner conductor and the outer conductor, wherein at least a portion of the inner conductor of the feedline extends through the chamber defined by the cylindrical sheath; and
a fluid flow tube extending through the chamber defined by the cylindrical sheath, the fluid flow tube configured to deliver a coolant fluid to the chamber defined by the cylindrical sheath to cool the portion of the inner conductor of the feedline extending through the chamber defined by the cylindrical sheath and to a proximal portion of the hub to cool the proximal portion of the hub.
2. The microwave antenna assembly according to claim 1 , wherein the coolant fluid is a gas.
3. The microwave antenna assembly according to claim 1 , wherein the coolant fluid is a liquid.
4. The microwave antenna assembly according to claim 1 , wherein the coolant fluid is a combination of a liquid and a gas.
5. The microwave antenna assembly according to claim 1 , further comprising:
a dielectric layer formed circumferentially about at least a portion of the outer conductor; and
a conductive layer formed circumferentially about at least a portion of the dielectric layer, at least a portion of the conductive layer electrically coupled to a portion of the outer conductor of the feedline, wherein the dielectric layer and the conductive layer limit propagation of microwave energy in a proximal direction.
6. The microwave antenna assembly according to claim 5 , wherein the conductive layer includes a proximal end electrically coupled to the outer conductor of the feedline.
7. The microwave antenna assembly according to claim 5 , wherein the dielectric layer and the conductive layer define a quarter wavelength choke.
8. The microwave antenna assembly according to claim 5 , further comprising a second dielectric layer formed circumferentially about the dielectric layer between the dielectric layer and the conductive layer.
9. The microwave antenna assembly according to claim 5 , wherein the feedline includes a radiating portion configured to deliver microwave energy to tissue and a distal end of the conductive layer is disposed proximal a proximal end of the radiating portion.
10. The microwave antenna assembly according to claim 1 , wherein the fluid flow tube extends through the hub.
11. The microwave antenna assembly according to claim 1 , wherein the fluid flow tube is disposed adjacent at least a portion of the inner conductor within the chamber defined by the cylindrical sheath.
12. The microwave antenna assembly according to claim 1 , wherein the feedline includes a radiating portion configured to deliver microwave energy to tissue and wherein a distal end of the fluid flow tube is disposed proximate the radiating portion.
13. The microwave antenna assembly according to claim 1 , further comprising a tip disposed at a distal portion of the microwave antenna assembly, wherein coolant fluid flow from the fluid tube is directed into the tip and reflected in a proximal direction.
14. The microwave antenna assembly according to claim 1 , further comprising a second fluid flow tube configured to deliver coolant, a distal end of the second flow tube disposed distal a distal end of the fluid flow tube.
15. The microwave antenna assembly according to claim 1 , wherein coolant flows in a first direction when flowing along an interior surface of the fluid flow tube and a second direction when flowing along an exterior surface of the fluid flow tube.
16. The microwave antenna assembly according to claim 1 , wherein the cylindrical sheath is a conducting cylindrical sheath formed of a conductive material.